1. Field of the Invention
The present invention relates to a vehicle brake drum. More specifically, the present invention relates to a vehicle brake drum having a squealer band where the squealer band has a plurality of fractures to provide increased vibration dampening for noise reduction.
2. Description of the Prior Art
Prior art methods to reduce the noise of squealing brake drums generated when the brakes are applied include adding a dampening material over the outer surface of the drum and/or fitting spring clips between the squealer band and the wheel to provide frictional dampening. The squealer band is comprised of an annular ring of material formed as part of the brake drum during the casting process usually positioned adjacent to the open end of the brake drum. The purpose of the squealer band is to attenuate brake squeal noise by altering the vibration characteristics of the brake drum. U.S. Pat. Nos. 5,383,538; 5,383,539 and 5,390,769 all assigned to same assignee, Eaton Corporation, as the present invention illustrate methods of reducing brake squeal by introducing additional frictional damping using clips or rings fitted between the wheel and the brake drum. One of the problems of the solution to increasing vibration damping as shown in the prior art, is with the number of additional parts and assembly complications due to the fitting of clips or a ring to the wheel/brake assembly. Also, as the clips lose tension due to heat cycling, the level of frictional dampening is reduced thereby increasing the brake squeal noise. Any method of permanently increasing dampening of the brake drum without the use of additional parts would lower cost and complexity while lowering the level of noise generated by brake squeal.